The Collaborative Initial Glaucoma Treatment Study (CIGTS), a National Eye Institute supported multicenter clinical trial, provided unique insights to how newly diagnosed open-angle glaucoma should be treated, whether by initial surgical or medical intervention. Even so, a wealth of clinically-relevant and important information to glaucoma and its treatment remains un-tapped in the extensive CIGTS data resource. Conduct of the proposed data analyses described in this grant application will provide unique, cost-effective opportunities to investigate additional research questions that are directly relevant to the management and care of patients who have open-angle glaucoma. We propose to conduct extensive analyses that address the following four specific aims: Specific Aim 1: To evaluate the impact that meeting a pre-set target intraocular pressure (IOP) has on long-term control of progression in visual field loss. Specific Aim 2: To determine the long-term IOP-reducing effect of argon laser trabeculoplasty (ALT), including the role that initial treatment, demographics, and clinical factors play, and the impact ALT has on visual function and quality of life. Specific Aim 3: To determine what factors are most important in an individual's assessment of the personal burden of glaucoma on his/her quality of life. Specific Aim 4: To describe symptom attribution to glaucoma or its treatment vs. other causes over time and explore clinical and demographic factors associated with changes in attribution.